Vibration energy harvesting moves forward

The periodic replacement of batteries is not feasible for embedded applications and is highly unattractive in wireless sensor networks containing hundreds of sensor nodes; harvesting vibration energy is the answer

Researchers at the University of Southampton’s School of Electronics & Computer Science (ECS) have developed a kinetic energy generator which generates electrical energy from the vibrations and movements present within its environment. “This is the most successful generator of its kind and generates energy much more efficiently than any similar device of its size,” said Dr. Steve Beeby, the team’s leader. It has been designed to power wireless sensors which monitor the condition of an industrial plant and is intended to be installed within an air compressor unit supplying several laboratories within a building. There are other commercial applications: It could be used in wireless, self-powered sensors and if developed further, could form the basis of technology for self-powered pace makers. The generator will be of interest not only to companies in the business of sensor networks, but also for security applications. As the need to monitor more and more facets of social and business life increases, the proliferation of sensor networks is only going to increase.

The technology holds the promise of augmenting batteries or replacing them altogether. The periodic replacement of batteries is not feasible for embedded applications (say, heart pacemakers) and is highly unattractive in wireless sensor networks containing hundreds of sensor nodes. “Vibration energy harvesting is receiving a considerable amount of interest as a means for powering wireless sensor nodes,” said Beeby. “The big advantage of wireless sensor systems is that by removing wires and batteries, there is the potential for embedding sensors in previously inaccessible locations.”

The generator, which is less than 1 cubic cm in size, was developed as part of the EU-funded EUR 4.13 million VIBES (Vibration Energy Scavenging) project.

There has been a growing interest in the field of low power miniature sensors and wireless sensor networks, but that interest has not been translated into much commercial activity because comparatively little attention has been paid to how to supply the required electrical power to such sensors, especially if the sensor is completely embedded in the structure with no physical connection to the outside world. He believes that the VIBES generator could hold the solution.

A paper entitled A micro electromagnetic generator for vibration energy harvesting about this research has just been published on the Journal of Micromechanics and Microengineering website.

Dr Beeby and his team plan to exploit this application further through Southampton, U.K.-based Perpetuum, the world-leading vibration energy-harvesting company which was formed in 2004 as a spin out from the University of Southampton.